Why are some LADSPA plugins unusable?

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I noticed that LADSPA plugins like Gverb come preinstalled inside LMMS, but they are labeled as "Unusable Effects"?
I tested Gverb on Carla and it works.

What exactly is the problem that stops LMMS from using certain preinstalled plugins?
Why even bother at bundling them inside the DAW if we can't use them?
Xeno Idaltu wrote:
Sun Oct 24, 2021 4:44 pm
I noticed that LADSPA plugins like Gverb come preinstalled inside LMMS, but they are labeled as "Unusable Effects"?
I tested Gverb on Carla and it works.

What exactly is the problem that stops LMMS from using certain preinstalled plugins?
Why even bother at bundling them inside the DAW if we can't use them?
gVerb is not in default collection. What version of LMMS do you use?